2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/104844Navier-Stokes equations are investigated in a functional setting in 3D open sets, bounded or not, without assuming any regularity of the boundary. The main idea is to find a correct definition of the Stokes operator in a suitable Hilbert space of divergence-free vectors and apply the Fujita-Kato method, a fixed point procedure, to get a local strong solution.5 pagesAnalysis of PDEsFunctional Analysis35Q30text